package cn.tedu.v6;

import sun.font.FontLineMetrics;

import java.io.*;
import java.net.*;
import java.util.*;

/**
 *Version 6  增加输入exit退出功能
 *
 */
public class Server {
    private ServerSocket serverSocket;
    private static final int PORT = 2356;
    private List<PrintWriter>allOut=new ArrayList<>();
    //1.存储在线客户：onlineUsers

    private List<String>onlineUsers=new ArrayList<>();

    private Map<String,String>userDatabase;

    public Server() {
        try {
            serverSocket = new ServerSocket(PORT);
            userDatabase=new HashMap<>();
            userDatabase.put("兰雅静","123456");
            userDatabase.put("小核桃","654321");
        } catch (BindException e) {
            System.out.println("端口号已经被占用");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void start() {
        try {
            while (true) {
                System.out.println("等待客户端连接");
                Socket socket = serverSocket.accept();

                new Thread(new ClientHandler(socket)).start();
            }
        } catch (IOException e) {
            System.out.println("客户端连接失效");
        } finally {
            if (serverSocket != null && serverSocket.isClosed()) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败~~~");
                }
                System.out.println("服务器关闭成功~~~Over");
            }
        }
    }
    public static void main(String[] args) {
        new Server().start();
    }


    private synchronized void broadcastMessage(String message){
        for (PrintWriter pw:allOut){
            pw.println("消息广播"+message);
        }
    }
//2.广播在线用户列表方法 updateOnlineUsers 更新在线人数
    //规则：没有参数、传入字符串保存所有的客户端名称
    //2.1 String userList="在线用户："+String.join("、",onlineUsers);
    //理解：拼接字符串，来客户名，记录一个客户端名
    //2.2 来一个客户端，分发一个客户端消息：用户名消息


private synchronized void UpdateOnlineUsers(){
    String userList="在线用户："+String.join("、",onlineUsers);
    broadcastMessage(userList);
}


    private class ClientHandler implements Runnable {
        private Socket socket;
        private String ip;
        private PrintWriter pw;
        private BufferedReader br;


        private String username;
        private String password;
        public ClientHandler(Socket s) {
            this.socket = s;
            ip = socket.getInetAddress().getHostAddress();
            try {
                br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF8"));
                pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(), "UTF8")), true);
                synchronized (allOut){
                    allOut.add(pw);
                }
            } catch (IOException e) {
                System.out.println("客户端断开连接");
            }
        }

        private void handleChat(){
            new Thread(() -> {
                try {
                    String message;
                    while ((message = br.readLine()) != null) {
                        System.out.println(ip+"客户端说：" + message);
                        System.out.print("服务器端请输入：");
                        if (message.equalsIgnoreCase("exit")){
                            break;
                        }
                        broadcastMessage(message);
                    }
                } catch (IOException e) {
                    System.out.println("客户端发的消息断开了");
                }
            }).start();


            Scanner input = new Scanner(System.in);
            while (true) {
                System.out.println("服务器请输入");
                String sme = input.nextLine();
                pw.println("服务器端说" + sme);
                if (sme.equalsIgnoreCase("exit")){
                    pw.println(username+"我退啦下次再见~~");
                    break;
                }
            }
        }


        private boolean Login(String user,String pass){
            return userDatabase.containsKey(user)&&userDatabase.get(user).equals(pass);
        }

        public void run() {
            try {
                pw.println("请输入用户名：");
                username = br.readLine();
                pw.println("请输入密码");
                password = br.readLine();
                if (Login(username,password)){
                    pw.println("登录成功，欢迎进入小兰聊天室");
                    //3.判断客户端连接成功---加入集合中   【同步块：监视对象---集合】
                    //3.1 客户端登陆成功---名字加入集合中   方法？

                  synchronized (onlineUsers){
                      onlineUsers.add(username);
                  }
                  UpdateOnlineUsers();

                    handleChat();
                }else{
                    pw.println("登录失败，用户名或密码错误");
                    socket.close();
                }

            }catch(IOException e){
                System.out.println("服务器端读写出问题");
            } finally {
              //4.同步块---从集合中依次移除用户名

                synchronized (allOut){
                    allOut.remove(pw);
                }
                if (pw != null)
                    pw.close();
                if (br != null)
                    try {
                        br.close();
                    } catch (IOException e) {
                        System.out.println("读入流断开连接");
                    }

                if (socket != null && !socket.isClosed()) {
                    System.out.println(ip + "一个客户端退出服务器连接~~");
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println(ip + "一个客户端退出链接异常~~");
                    }
                }
            }
        }
    }
}
